Manuel Balce Ceneta/AP

Senior Department of Homeland Security officials, current and former, are reacting with optimism to word that retired Marine Corps Gen. John Kelly is President-elect Donald Trump’s choice to lead their agency, including some of Trump’s fiercest critics.

“When you have 4-stars who have been combatant commanders, they are generally the most broadly experienced people in government,” said Michael Chertoff, who served as the department’s second-ever secretary in the Bush administration. “You’re kind of a warrior-diplomat, not just a warrior.”

Chertoff was one of more than 70 national security veterans of the Bush administration who called Trump unfit to lead, in an open letter in March, but has taken heart over the nominations of retired Lt. Gen. Michael Flynn to be National Security Adviser, Marine Corps Gen. James Mattis to lead the Pentagon, and the reported choice of Kelly to DHS.

“I have to say these national security appointments are positive and give me a much bigger feeling of encouragement about the direction of the administration,” he said in an interview.

“I’m positive about it,” said former Congresswoman Jane Harman who now directs the Woodrow Wilson Center. “He’s highly regarded in the military and worked his way up. He has a close personal relationships with [Homeland Security Secretary] Jeh Johnson.”

“All this helps build a national security team,” said the former California Democrat, who has championed DHS reform, in an interview Thursday.

Adding a third general to the Trump cabinet may soothe an American public distrustful of politicians and fearful of terrorists. But Homeland Security veterans say even a storied, retired four-star general will struggle to manage legal and illegal traffic at the Mexican border, spot would-be terrorists in American communities, and most of all, deal with Congress.

Known as a blunt-speaking strategic thinker, Kelly served more than 40 years in the Marines including commanding in Iraq. He carries the heart-breaking distinction of being a Gold Star father, after losing his son, Marine 1st Lt. Robert Kelly, in Afghanistan in 2010.

Kelly has experience helping police the southern seas and border, as he retired from running U.S. Southern Command earlier this year, after butting heads with the Obama administration over issues like closing the U.S. military detention facility at Guantanamo Bay, which he opposed.

In his SouthCom role, Kelly decried the crime and instability south of the border that was driving people north – and repeatedly warned that terrorists could use that flow to attack the U.S. homeland.

“The relative ease with which human smugglers moved tens of thousands of people to our nation’s doorstep also serves as another warning sign: these smuggling routes are a potential vulnerability to our homeland,” he said, testifying before Congress. “Terrorist organizations could seek to leverage those same smuggling routes to move operatives with intent to cause grave harm to our citizens or even bring weapons of mass destruction into the United States.”

That kind of testimony grated on the Obama administration but tracks nicely with Trump’s “build a wall” mantra, though Department of Homeland Security Secretary Jeh Johnson points out that 700 miles of the 2000-mile border already have some sort of fence or wall, and the rest is fairly mountainous or has some other sort of natural barrier that makes it hard to cross.

A former senior DHS official said Kelly’s role commanding a Florida-based interagency task force that blends the efforts of the military, Coast Guard, and law enforcement will be great training for the job—but the former official said that he’s going to have to get used to playing alongside other agencies rather than being in charge, which in the past has stymied solutions at the border with Mexico.

“When you try to replicate that on the border, you end up with FBI, Justice, DHS and DoD and everyone wants to be in charge,” the official said of previous efforts. “Nobody owns the problem so nobody takes charge of solving it.”

Harman thought Kelly would have the charisma to solve that.

“I think who is in charge will be clarified,” she said. “I think this guy has enormous credibility that he will get the lead assignment on the border.”

Kelly is also taking charge of a department where morale is notoriously low, partly because it loses people who get frustrated with their inability to bring good ideas to fruition – often because they can’t get the funding or legislation needed to carry out those ideas through Congress.

When the Department of Homeland Security was established in 2002 after the attacks of 9/11 on New York and Washington, D.C., it was supposed to break down the stovepipes between 22 federal agencies and streamline the U.S. national security apparatus.

“I’m a godmother of DHS, which is an overweight child greatly in need of going to the gym,” said Harman, who served on the House homeland security committee, armed services and intelligence committees, overseeing post-9/11 reform of DHS. “Employee morale has always been low, because 22 agencies is a lot to put in one box.”

And the one 9/11 Commission reform that hasn’t been carried out in the wake of the attacks, Harman said, is streamlining who has jurisdiction over DHS.

“It’s a complete nightmare,” she said.

More than 90 committees and subcommittees can claim the right to question DHS officials and look over legislation.

That means the DHS chiefs often feel like they spend as much time testifying and preparing to testify as getting things done. The agency has never had a budget passed by Congress since it was created, which means it lives on year-to-year funding that frustrates projects that require multiple years of funding to complete.

“Since January 2015, our people in DHS have testified in 208 hearings of committees and subcommittees, (providing) 299 witnesses,” current DHS Secretary Johnson told an audience at the Washington, D.C.-based Bipartisan Policy Center, which is dedicated to post-9/11 reform. “We've had 4,010 non-hearing Congressional engagements,” with Johnson himself testifying 26 times in three years.

“When you're constantly testifying on the Hill before multiple committees and subcommittees, it's kind of hard to do your job,” said House Homeland Security Chairman Michael McCaul at the Bipartisan Policy Forum in Washington, D.C., last week in answer to a Daily Beast question. It was a rare moment of agreement for a Republican with an Obama administration official. “I think it paralyzes the Department from its core mission of protecting the American people.”

McCaul also interviewed with President-elect Trump in a bid to lead the department. He confirmed to The Daily Beast that he hoped to take up the post, but his staff offered no comment to the news Kelly would instead get the nod.

As for “fixing the border,” DHS officials current and former say the real problem is not the illegal immigration, which actually dropped in numbers in recent years, largely due to an ailing economy – but to the continuing surge of would-be immigrants who arrive at a U.S. border checkpoint with no identity papers, and demand asylum.

“Detention centers for full and the process for adjudicating these claims takes forever,” the former DHS official said. “That’s his job to figure out together with Congress.” Johnson said there are 41,000 people in immigration detention facilities. There are also roughly half-a-million cases already pending in immigration court.

Johnson said the DHS arm devoted to deporting aliens (a deportation force that Trump has called for, which already exists) has been focusing on kicking out convicted criminals first.

“The numbers of deportations have gone down over the last four years, but the percentage of those deported who are convicted criminals has gone up to something over 60 percent,” Johnson said. “In immigration detention today, something like 90 percent fit one of our removal priorities.”

More than 408,000 people were detained at the border with Mexico in (Fiscal Year) 2016 by the U.S. Border Patrol. From years 2000-2008 under the Bush administration, yearly detentions ranged from three-quarters of a million people to more than a million, which Obama administration officials say shows they’ve been tough on illegal immigration.

But hundreds keep arriving at U.S. border checkpoints each day.

Another tough task ahead – countering what the Obama administration calls violent extremism (or Islamic militancy, as Trump officials call it) in American communities. That’s a task made tougher by Trump’s campaign language and that of his prospective National Security Adviser Flynn, who has equated Islam with cancer and tweeted that “Fear of Muslims is RATIONAL.”

Trump has since tempered his call for a ban on Muslims entering the country to what he calls “extreme vetting.” McCaul, who has been in discussions with the Trump transition team, described that as more thorough checks and restrictive procedures applied to people in countries where terrorism has taken root.

“You can't condemn Islam in general,” McCaul said. “But what we do target is radical Islamists….It's important that we identify that and not be so politically correct that we can't identify the threat for what it is, and then target that in your vetting process.”

But the original more imprecise language that targeted all of Islam has been seized by the so-called Islamic State and other fringe militant groups as a rallying cry to recruit Muslims in the west to attack at home.

Such shoot-from-the-hip rhetoric may eventually drive Trump’s generals out.

“I think they’re all gonna say ‘What the hell did Donald trump tweet last night?” the senior DHS official said. “They’re not going to put up with that. They’re not going to be jerked around for too long.”